1. Technical Field
The present disclosure relates to coating technology, and particularly to a gas-inputting device for a vacuum sputtering apparatus.
2. Description of Related Art
Generally, during sputter-coating of a number of workpieces such as cell phone housings. An inert gas is injected into a sputter-coating chamber via a gas-inputting device to release energized ions. The energized ions bombard a solid target material to vaporize the material. The vaporized material is then deposited on the workpieces. The gas-inputting device includes a number of tubes with different length. The tubes are parallel to each other. Each tube has a first end connected to a gas source, and an opposite second end disposed at different height of the sputter-coating chamber for inputting the inert gas into the sputter-coating chamber. However, the amount of the inert gas inputted from different length tubes is different because the pressure of the inert gas injected into the sputter-coating chamber from the first end to the second end will decrease as the length of the tubes increases. The shorter tube has a higher gas pressure, and outputs more inert gas. The longer tube has a lower gas pressure, and outputs less inert gas. Therefore, the gas density of the inert gas at a higher position will be higher than that at a lower position. The non-uniform gas density of the inert gas will affect the coating quality of the workpiece.
What is needed, therefore, is a gas-inputting device for a vacuum sputtering apparatus to overcome the above-described problem.